Effect of Soil Temperature at Different Growth Stages on Growth and Development of Potato Plants 1

1966 ◽  
Vol 58 (2) ◽  
pp. 169-171 ◽  
Author(s):  
Eliot Epstein
2016 ◽  
Vol 52 (No. 4) ◽  
pp. 262-269 ◽  
Author(s):  
Gao Feng ◽  
Zhao Zi-Hua ◽  
Jifon John ◽  
Liu Tong-Xian

The impact of vector density and timing of infestation on potato were investigated. Healthy potato plants at different growth stages (4, 5, and 7 weeks after germination) were exposed separately to four different B. cockerelli densities (0, 5, 20, and 40 psyllids per cage) in field cages and Zebra chip (ZC) symptoms, leaf photosynthetic rates, tuber yield, and total nonstructural carbohydrate accumulation in leaves and tubers of healthy and B. cockerelli-infested plants were monitored. Potato psyllid nymph and egg populations reached a seasonal peak at 6 weeks after the exposure to insect. Younger plants at 4-week growth stage after germination were more susceptible to B. cockerelli infestation and ZC expression than older plants. As few as five B. cockerelli adults were enough to transmit the ZC pathogen and cause ZC expression both in foliage and tuber. At the density of 20 psyllids per cage, more than 50% of plants showed ZC symptoms in tubers. Furthermore, B. cockerelli infestation reduced leaf photosynthesis rates (P<sub>n</sub>), resulting in less starch and more reducing sugars in tubers, and hence reduced tuber weight and yield, especially when psyllid infestation occurred at the early growth stages. The results indicate that early B. cockerelli infestation of younger plants was associated with more severe ZC expression in both foliage and tubers, leading to earlier dead plants. The data suggest that strategies for controlling B. cockerelli during early potato crop development could thus lessen the severity of ZC development.


Weed Science ◽  
2009 ◽  
Vol 57 (6) ◽  
pp. 584-592 ◽  
Author(s):  
Uliana B. Bashtanova ◽  
K. Paul Beckett ◽  
Timothy J. Flowers

Japanese knotweed is an aggressive alien species in Europe, North America, and Australia, causing a range of environmental problems. Eradication of Japanese knotweed is proving to be a difficult task, because the plant is able to propagate generatively by intra- and interspecific hybridization, and vegetatively from shoot and tiny rhizome pieces. Despite the economic consequences of Japanese knotweed on natural and built environments, its physiology is not yet fully understood; especially important are sink-source relations between old and young parts of the rhizome and growth of lateral and latent rhizome buds. Current methods of chemical control include three types of phloem-mobile herbicides, such as glyphosate, imazapyr, and synthetic auxins. These herbicides have limitations on their use, and all fail to eradicate the plant completely, for the reasons discussed in this review. Our aim is to suggest prospective approaches to enable chemical eradication: use of signals to induce controlled growth and development of quiescent rhizome buds; use of phytohormones, sugars, and light to increase allocation of phloem-mobile herbicides to the rhizome; use of xylem-mobile herbicides to exterminate the old rhizome parts; and use of different phloem-mobile herbicides at different growth stages.


1996 ◽  
Vol 10 (2) ◽  
pp. 247-252 ◽  
Author(s):  
Erik D. Wilkins ◽  
Robin R. Bellinder

Field studies determined the influence of developmental stage on mow-killing of winter wheat and rye. Both crops were clipped at either three or four different growth stages in 1992 and 1993. When mowed at first node, wheat biomass was 4350 and 1970 kg/ha in 1992 and 1993, respectively. At this stage, primary tiller apices were below 10 cm and regrowth was vigorous. Mowing prior to 75% heading consistently yielded more than 1000 kg/ha regrowth 8 wk later. Wheat cut after flowering produced 15 460 and 9160 kg/ha dry matter in 1992 and 1993, respectively, but less than 30 kg/ha total regrowth. At first and second node, rye produced 4440 and 1800 kg/ha biomass in 1992 and 1993. When mowed belore boot, more than 50% of the total rye biomass was due to regrowth. Rye mowed at boot yielded 6940 and 3740 kg/ha in 1992 and 1993 respectively, and regrowth measured 780 and 910 kg/ha 8 wk later. Mowing after flowering resulted in no measurable regrowth. Soil temperature and PAR were affected by mow-kill date and biomass. Biomass at first mowings (first and second node) in both wheat and rye reduced seasonal soil temperatures 3.5 C compared to bare soil temperatures; while biomass at kernal-filling lowered temperatures 6.0 C. Measured 8 wk after mowing, first node mowings absorbed between 55% and 70% PAR, while plants mowed at kernal-filling absorbed less than 5%.


Genes ◽  
2020 ◽  
Vol 11 (10) ◽  
pp. 1228
Author(s):  
Zhigang Hu ◽  
Junting Cao ◽  
Guangyu Liu ◽  
Huilin Zhang ◽  
Xiaolin Liu

In China, the production for duck meat is second only to that of chicken, and the demand for duck meat is also increasing. However, there is still unclear on the internal mechanism of regulating skeletal muscle growth and development in duck. This study aimed to identity candidate genes related to growth of duck skeletal muscle and explore the potential regulatory mechanism. RNA-seq technology was used to compare the transcriptome of skeletal muscles in black Muscovy ducks at different developmental stages (day 17, 21, 27, 31, and 34 of embryos and postnatal 6-month-olds). The SNPs and InDels of black Muscovy ducks at different growth stages were mainly in “INTRON”, “SYNONYMOUS_CODING”, “UTR_3_PRIME”, and “DOWNSTREAM”. The average number of AS in each sample was 37,267, mainly concentrated in TSS and TTS. Besides, a total of 19 to 5377 DEGs were detected in each pairwise comparison. Functional analysis showed that the DEGs were mainly involved in the processes of cell growth, muscle development, and cellular activities (junction, migration, assembly, differentiation, and proliferation). Many of DEGs were well known to be related to growth of skeletal muscle in black Muscovy duck, such as MyoG, FBXO1, MEF2A, and FoxN2. KEGG pathway analysis identified that the DEGs were significantly enriched in the pathways related to the focal adhesion, MAPK signaling pathway and regulation of the actin cytoskeleton. Some DEGs assigned to these pathways were potential candidate genes inducing the difference in muscle growth among the developmental stages, such as FAF1, RGS8, GRB10, SMYD3, and TNNI2. Our study identified several genes and pathways that may participate in the regulation of skeletal muscle growth in black Muscovy duck. These results should serve as an important resource revealing the molecular basis of muscle growth and development in duck.


2021 ◽  
Vol 13 (3) ◽  
pp. 411
Author(s):  
Hassan Afzaal ◽  
Aitazaz A. Farooque ◽  
Arnold W. Schumann ◽  
Nazar Hussain ◽  
Andrew McKenzie-Gopsill ◽  
...  

This study evaluated the potential of using machine vision in combination with deep learning (DL) to identify the early blight disease in real-time for potato production systems. Four fields were selected to collect images (n = 5199) of healthy and diseased potato plants under variable lights and shadow effects. A database was constructed using DL to identify the disease infestation at different stages throughout the growing season. Three convolutional neural networks (CNNs), namely GoogleNet, VGGNet, and EfficientNet, were trained using the PyTorch framework. The disease images were classified into three classes (2-class, 4-class, and 6-class) for accurate disease identification at different growth stages. Results of 2-class CNNs for disease identification revealed the significantly better performance of EfficientNet and VGGNet when compared with the GoogleNet (FScore range: 0.84–0.98). Results of 4-Class CNNs indicated better performance of EfficientNet when compared with other CNNs (FScore range: 0.79–0.94). Results of 6-class CNNs showed similar results as 4-class, with EfficientNet performing the best. GoogleNet, VGGNet, and EfficientNet inference time values ranged from 6.8–8.3, 2.1–2.5, 5.95–6.53 frames per second, respectively, on a Dell Latitude 5580 using graphical processing unit (GPU) mode. Overall, the CNNs and DL frameworks used in this study accurately classified the early blight disease at different stages. Site-specific application of fungicides by accurately identifying the early blight infected plants has a strong potential to reduce agrochemicals use, improve the profitability of potato growers, and lower environmental risks (runoff of fungicides to water bodies).


Animals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 834
Author(s):  
Zhigang Hu ◽  
Junting Cao ◽  
Liyan Ge ◽  
Jianqin Zhang ◽  
Huilin Zhang ◽  
...  

Skeletal muscle, accounting for approximately 50% of body weight, is the largest and most important tissue. In this study, the gene expression profiles and pathways in skeletal muscle of Pekin duck were investigated and compared at embryonic day 17, 21, and 27 and postnatally at 6 months of age. An average of 49,555,936 reads in each sample was obtained from the transcriptome libraries. Over 70.0% of alternative splicing (AS) in each sample was mainly alternative 5’ first exon (transcription start site)-the first exon splicing (TSS) and alternative 3’ last exon (transcription terminal site)-the last exon splicing (TTS), indicating that TSS and TTS were the most common AS event in Pekin ducks, and these AS events were closely related to the regulation of muscle development at different growth stages. The results provided a valuable genomic resource for selective breeding and functional studies of genes. A total of 299 novel genes with ≥2 exons were obtained. There were 294 to 2806 differentially expressed genes (DEGs) in each pairwise comparison of Pekin duck. Notably, 90 DEGs in breast muscle and 9 DEGs in leg muscle were co-expressed at all developmental points. DEGs were validated by qPCR analysis, which confirmed the tendency of the expression. DEGs related to muscle development were involved in biological processes such as “endodermal cell differentiation”, “muscle cell cellular homeostasis”, “skeletal muscle tissue growth” and “skeletal muscle cell differentiation”, and were involved in pathways such as oxidative phosphorylation, ECM-receptor (extracellular matrix receptor) interaction, focal adhesion, carbon metabolism, and biosynthesis of amino acids. Some DEGs, including MYL4, IGF2BP1, CSRP3, SPP1 and KLHL31, as well as LAMB2, LAMA2, ITGB1 and OPN, played crucial roles in muscle growth and development. This study provides valuable information about the expression profile of mRNAs and pathways from duck skeletal muscle at different growth stages, and further functional study of these mRNAs and pathways could provide new ideas for studying the molecular networks of growth and development in duck skeletal muscle.


1997 ◽  
Vol 99 (1) ◽  
pp. 185-189
Author(s):  
Wen-Shaw Chen ◽  
Kuang-Liang Huang ◽  
Hsiao-Ching Yu

2013 ◽  
Vol 39 (5) ◽  
pp. 919 ◽  
Author(s):  
Bo MING ◽  
Jin-Cheng ZHU ◽  
Hong-Bin TAO ◽  
Li-Na XU ◽  
Bu-Qing GUO ◽  
...  

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